Anomaly detection search for new resonances decaying into a Higgs boson and a generic new particle X in hadronic final states using √s=13 TeV pp collisions with the ATLAS detector

• Titel: Anomaly detection search for new resonances decaying into a Higgs boson and a generic new particle X in hadronic final states using √s=13 TeV pp collisions with the ATLAS detector
• Mitwirkende: Aad, Georges [VerfasserIn]
• Mitwirkende: Baltes, Lisa Marie [VerfasserIn]
• Mitwirkende: Bartels, Falk [VerfasserIn]
• Mitwirkende: Castillo, Florencia Luciana [VerfasserIn]
• Mitwirkende: Czurylo, Marta [VerfasserIn]
• Mitwirkende: Dittmeier, Sebastian [VerfasserIn]
• Mitwirkende: Dunford, Monica [VerfasserIn]
• Mitwirkende: Franchino, Silvia [VerfasserIn]
• Mitwirkende: Klassen, Martin [VerfasserIn]
• Mitwirkende: Mkrtchyan, Tigran [VerfasserIn]
• Mitwirkende: Ott, Philipp [VerfasserIn]
• Mitwirkende: Rassloff, Damir Fabrice [VerfasserIn]
• Mitwirkende: Rodriguez Bosca, Sergi [VerfasserIn]
• Mitwirkende: Sauer, Christof [VerfasserIn]
• Mitwirkende: Schöning, André [VerfasserIn]
• Mitwirkende: Schultz-Coulon, Hans-Christian [VerfasserIn]
• Mitwirkende: Sothilingam, Varsiha [VerfasserIn]
• Mitwirkende: Stamen, Rainer [VerfasserIn]
• Mitwirkende: Starovoitov, Pavel [VerfasserIn]
• Mitwirkende: Vigani, Luigi [VerfasserIn]
• Mitwirkende: Weber, Sebastian [VerfasserIn]
• Mitwirkende: Wessels, Martin [VerfasserIn]
• Mitwirkende: Zinßer, Joachim [VerfasserIn]
• Körperschaft: ATLAS Collaboration [VerfasserIn]
• Verf.angabe: G. Aad et al. (ATLAS Collaboration*)
• E-Jahr: 2023
• Jahr: 1. September 2023
• Umfang: 33 S.
• Illustrationen: Illustrationen
• Fussnoten: Online veröffentlicht: 18. September 2023 ; *ATLAS Collaboration: G. Aad, L.M. Baltes, F. Bartels, F.L. Castillo, M.M. Czurylo, M. Dunford, S. Franchino, M. Klassen, T. Mkrtchyan, P.S. Ott, D.F. Rassloff, S. Rodriguez Bosca, C. Sauer, A. Schoening, H-C. Schultz-Coulon, V. Sothilingam, R. Stamen, P. Starovoitov, L. Vigani, S.M. Weber, M. Wessels, J. Zinsser [und 2914 weitere Personen] ; Im Titel steht der Buchstabe s unter dem Wurzelsymbol ; Gesehen am 17.05.2024
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Ridge, NY : American Physical Society, 2016
• Jahr Quelle: 2023
• Band/Heft Quelle: 108(2023), 5 vom: Sept., Artikel-ID 052009, Seite 1-33
• ISSN Quelle: 2470-0029
• DOI: doi:10.1103/PhysRevD.108.052009
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1889101133

Abstract

A search is presented for a heavy resonance Y decaying into a Standard Model Higgs boson H and a new particle X in a fully hadronic final state. The full Large Hadron Collider run 2 dataset of proton-proton collisions at √s=13 TeV collected by the ATLAS detector from 2015 to 2018 is used and corresponds to an integrated luminosity of 139 fb−1. The search targets the high Y-mass region, where the H and X have a significant Lorentz boost in the laboratory frame. A novel application of anomaly detection is used to define a general signal region, where events are selected solely because of their incompatibility with a learned background-only model. It is constructed using a jet-level tagger for signal-model-independent selection of the boosted X particle, representing the first application of fully unsupervised machine learning to an ATLAS analysis. Two additional signal regions are implemented to target a benchmark X decay into two quarks, covering topologies where the X is reconstructed as either a single large-radius jet or two small-radius jets. The analysis selects Higgs boson decays into b¯b, and a dedicated neural-network-based tagger provides sensitivity to the boosted heavy-flavor topology. No significant excess of data over the expected background is observed, and the results are presented as upper limits on the production cross section σ(pp→Y→XH→q¯qb¯b) for signals with mY between 1.5 and 6 TeV and mX between 65 and 3000 GeV.